/*
 *  WSO2 Inc. licenses this file to you under the Apache License,
 *  Version 2.0 (the "License"); you may not use this file except
 *  in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.wso2.balana.xacml3;

import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.wso2.balana.ParsingException;
import org.wso2.balana.XACMLConstants;

import java.net.URI;
import java.util.HashSet;
import java.util.Set;

/**
 * Represents the MultiRequestsType XML type found in the context schema.
 */
public class MultiRequests {

	/**
	 * <code>Set</code> of <code>RequestReference</code> that contains in
	 * <code>MultiRequests</code>
	 */
	private Set<RequestReference> requestReferences;

	/**
	 * Constructor that creates a new <code>MultiRequests</code> based on the
	 * given elements.
	 * 
	 * @param requestReferences
	 *            <code>Set</code> of <code>RequestReference</code>
	 */
	private MultiRequests(Set<RequestReference> requestReferences) {
		this.requestReferences = requestReferences;
	}

	/**
	 * creates a <code>MultiRequests</code> based on its DOM node.
	 * 
	 * @param root
	 *            root the node to parse for the AttributeAssignment
	 * @return a new <code>MultiRequests</code> constructed by parsing
	 * @throws ParsingException
	 *             if the DOM node is invalid
	 */
	public static MultiRequests getInstance(Node root) throws ParsingException {

		Set<RequestReference> requestReferences = new HashSet<RequestReference>();

		// First check that we're really parsing an MultiRequests
		if (!root.getNodeName().equals("MultiRequests")) {
			throw new ParsingException(
					"MultiRequests object cannot be created "
							+ "with root node of type: " + root.getNodeName());
		}

		NodeList nodes = root.getChildNodes();
		for (int i = 0; i < nodes.getLength(); i++) {
			Node node = nodes.item(i);
			if ("RequestReference".equals(node.getNodeName())) {
				Set<AttributesReference> attributesReferences = new HashSet<AttributesReference>();
				RequestReference requestReference = new RequestReference();
				NodeList childNodes = node.getChildNodes();
				for (int j = 0; j < childNodes.getLength(); j++) {
					Node childNode = childNodes.item(i);
					if ("AttributesReference".equals(childNode.getNodeName())) {
						AttributesReference attributesReference = new AttributesReference();
						attributesReferences.add(attributesReference);
						NamedNodeMap nodeAttributes = root.getAttributes();
						try {
							String referenceId = nodeAttributes.getNamedItem(
									"ReferenceId").getNodeValue();
							attributesReference.setId(referenceId);
						} catch (Exception e) {
							throw new ParsingException(
									"Error parsing required ReferenceId in "
											+ "MultiRequestsType", e);
						}
					}
				}

				if (attributesReferences.isEmpty()) {
					throw new ParsingException(
							"RequestReference must contain at least one "
									+ "AttributesReference");
				}
				requestReference.setReferences(attributesReferences);
				requestReferences.add(requestReference);
			}
		}

		if (requestReferences.isEmpty()) {
			throw new ParsingException(
					"MultiRequests must contain at least one RequestReference");
		}

		return new MultiRequests(requestReferences);
	}

	/**
	 * returns <code>Set</code> of <code>RequestReference</code>
	 * 
	 * @return <code>Set</code> of <code>RequestReference</code>
	 */
	public Set<RequestReference> getRequestReferences() {
		return requestReferences;
	}
}
